Gaige

"Accuracy is what you train your eyes on if you're worried about low damage."

- Gaige to Matt

Gaige is a Vault Hunter known as the Mechromancer. She is a main supporting character in Someone Else, and was upgraded to deuteragonist in the sequel, No One Else. Gaige was the first to meet Matt Rye, following a run-in with some bandits who followed her from the Dust to the Highlands. A master mechanic, Gaige was able to build a robot, D374-TP, or Deathtrap.

Pre-Borderlands 2
Gaige was a high school student from the planet Eden-5. She originally conceived Deathtrap, then called DT, as a science fair project to combat bullying. Her rival, Marcie Holloway, was a contestant in the science fair as well, and used her father's money to buy her way through the competition. Marcie apparently stole Gaige's DT designs and sold them to Eden-5's police force.

On the day of the science fair, Marcie's father bribed the judges, helping win her first place with a defective robot based on Deathtrap's blueprints. Gaige placed third. Marcie then shoved Gaige, causing Deathtrap to identify her as a hostile. Deathtrap attacked with its claws, causing her to explode due to a miscalculation in its calibration by Gaige. Gaige was escorted to the principal's office, and faced expulsion and arrest for accidentally murdering her rival. She called her father to create a distraction to help her evade arrest, and bought a ticket to Pandora, where she stowed away on a train leading to Windshear Waste.

Borderlands 2
Gaige was on board the train when Handsome Jack blew it up, intending to kill the Vault Hunters. She survived the explosion, and was rescued from the wreckage half-alive by Axton and Maya, as well as the rest of the surviving Vault Hunters who had boarded the train. Claptrap handed her an ECHO device, while Axton asked if she was Vault Hunter too. Abashed, and reluctant to admit her origins, she lied and claimed she was. Axton immediately detected her lie, but Gaige assured them she would explain herself once they were in a safer and warmer area.

Once they arrived in Sanctuary, Gaige explained that she was merely an 18-year-old high school student who boarded the train to escape her charges on Eden-5. After killing Knuckledragger, Gaige received the Hornet and the group went on their way to Santuary.

Ultimately, they succeeded and arrived in Sanctuary and joined the Crimson Raiders. Gaige's joining was argued over by Lilith and Axton, however Lilith ultimately agreed to allow Gaige, now having given herself the title of "the Mechromancer", to join the Raiders.

Gaige was vital in the mission to defeat Handsome Jack due to her mechanics and tech skills, which provided the Raiders a major leg-up on their missions. She was present for the final battle against Jack in the Vault of the Warrior, and was one of the few Vault Hunters who did not argue about Lilith killing Jack - likely because she had the least qualms with the man. Gaige then returned to Sanctuary with her allies to discuss the next step of their mission.